The most common and most likely answer to this crossword clue is the 8 letter word PLUMMETS
I've seen this crossword clue in Financial Times
P
L
U
M
M
E
T
S
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The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does PLUMMETS mean?
PLUMMETS noun- A piece of lead attached to a line, used in sounding the depth of water, a plumb bob or a plumb line
- Hence, any weight
- A piece of lead formerly used by school children to rule paper for writing (that is, to mark with rules, with lines)
- A plummet line, a line with a plummet; a sounding line
- Violent or dramatic fall
- A decline; a fall; a drop
- To drop swiftly, in a direct manner; to fall quickly.